期刊文献+
共找到6,523篇文章
< 1 2 250 >
每页显示 20 50 100
Modeling and Analysis of Submerged Arc Weld Power Supply Based on Double Closed-Loop Control
1
作者 Baoshan Shi Kuanfang He +1 位作者 Xuejun Li Dongmin Xiao 《Journal of Software Engineering and Applications》 2010年第7期723-727,共5页
According to the soft-switching pulsed SAW (Submerged arc weld) weld power supply based on the double closed-loop constant current control mode, a small signal mathematic model of main circuit of soft-switching SAW in... According to the soft-switching pulsed SAW (Submerged arc weld) weld power supply based on the double closed-loop constant current control mode, a small signal mathematic model of main circuit of soft-switching SAW inverter was established by applying the method of three-terminal switching device modeling method, and the math-ematic model of double closed-loop phase-shift control system circuit was established by applying the method of state-space averaging method. Dynamic performance of the inverter was analyzed on base of the established math-ematic model, and the tested wave of dynamic performance was shown by experimentation. Research and experimentation show that relation between structure of the power source circuit and dynamic performance of the controlling system can be announced by the established mathematic model, which provides development of power supply and optimized design of controlling parameter with theoretical guidance. 展开更多
关键词 SAW double LOOP control SOFT-SWITCHING Inverter Mathematic Model
下载PDF
A Double-Interactively Recurrent Fuzzy Cerebellar Model Articulation Controller Model Combined with an Improved Particle Swarm Optimization Method for Fall Detection
2
作者 Jyun-Guo Wang 《Computer Systems Science & Engineering》 2024年第5期1149-1170,共22页
In many Eastern and Western countries,falling birth rates have led to the gradual aging of society.Older adults are often left alone at home or live in a long-term care center,which results in them being susceptible t... In many Eastern and Western countries,falling birth rates have led to the gradual aging of society.Older adults are often left alone at home or live in a long-term care center,which results in them being susceptible to unsafe events(such as falls)that can have disastrous consequences.However,automatically detecting falls fromvideo data is challenging,and automatic fall detection methods usually require large volumes of training data,which can be difficult to acquire.To address this problem,video kinematic data can be used as training data,thereby avoiding the requirement of creating a large fall data set.This study integrated an improved particle swarm optimization method into a double interactively recurrent fuzzy cerebellar model articulation controller model to develop a costeffective and accurate fall detection system.First,it obtained an optical flow(OF)trajectory diagram from image sequences by using the OF method,and it solved problems related to focal length and object offset by employing the discrete Fourier transform(DFT)algorithm.Second,this study developed the D-IRFCMAC model,which combines spatial and temporal(recurrent)information.Third,it designed an IPSO(Improved Particle Swarm Optimization)algorithm that effectively strengthens the exploratory capabilities of the proposed D-IRFCMAC(Double-Interactively Recurrent Fuzzy Cerebellar Model Articulation Controller)model in the global search space.The proposed approach outperforms existing state-of-the-art methods in terms of action recognition accuracy on the UR-Fall,UP-Fall,and PRECIS HAR data sets.The UCF11 dataset had an average accuracy of 93.13%,whereas the UCF101 dataset had an average accuracy of 92.19%.The UR-Fall dataset had an accuracy of 100%,the UP-Fall dataset had an accuracy of 99.25%,and the PRECIS HAR dataset had an accuracy of 99.07%. 展开更多
关键词 double interactively recurrent fuzzy cerebellar model articulation controller(D-IRFCMAC) improved particle swarm optimization(IPSO) fall detection
下载PDF
基于Dueling Double DQN的交通信号控制方法
3
作者 叶宝林 陈栋 +2 位作者 刘春元 陈滨 吴维敏 《计算机测量与控制》 2024年第7期154-161,共8页
为了提高交叉口通行效率缓解交通拥堵,深入挖掘交通状态信息中所包含的深层次隐含特征信息,提出了一种基于Dueling Double DQN(D3QN)的单交叉口交通信号控制方法;构建了一个基于深度强化学习Double DQN(DDQN)的交通信号控制模型,对动作... 为了提高交叉口通行效率缓解交通拥堵,深入挖掘交通状态信息中所包含的深层次隐含特征信息,提出了一种基于Dueling Double DQN(D3QN)的单交叉口交通信号控制方法;构建了一个基于深度强化学习Double DQN(DDQN)的交通信号控制模型,对动作-价值函数的估计值和目标值迭代运算过程进行了优化,克服基于深度强化学习DQN的交通信号控制模型存在收敛速度慢的问题;设计了一个新的Dueling Network解耦交通状态和相位动作的价值,增强Double DQN(DDQN)提取深层次特征信息的能力;基于微观仿真平台SUMO搭建了一个单交叉口模拟仿真框架和环境,开展仿真测试;仿真测试结果表明,与传统交通信号控制方法和基于深度强化学习DQN的交通信号控制方法相比,所提方法能够有效减少车辆平均等待时间、车辆平均排队长度和车辆平均停车次数,明显提升交叉口通行效率。 展开更多
关键词 交通信号控制 深度强化学习 Dueling double DQN Dueling Network
下载PDF
Reinforced temperature control of a reactive double dividing-wall distillation column
4
作者 Wei Qin Lijing Zang +5 位作者 Kejin Huang Haisheng Chen Yang Yuan Xing Qian Liang Zhang Shaofeng Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期288-295,共8页
The mass and thermal coupling makes the control of the reactive double dividing-wall distillation column(R-DDWDC) an especially challenging issue with a highly interactive nature. With reference to the separation of a... The mass and thermal coupling makes the control of the reactive double dividing-wall distillation column(R-DDWDC) an especially challenging issue with a highly interactive nature. With reference to the separation of an ideal endothermic quaternary reversible reaction with the most unfavorable ranking of relative volatilities(A + B ■ C + D with α_(A)>α_(C)>α_(D)>α_(B)), the operation rationality of the R-DDWDC is studied in this contribution. The four-point single temperature control system leads to great steady-state discrepancies in the compositions of products C and D and the reason stems essentially from the failure in keeping strictly the stoichiometric ratio between reactants A and B. A temperature plus temperature cascade control scheme is then employed to reinforce the stoichiometric ratio control and helps to secure a substantial abatement in the steady-state discrepancies. A temperature difference plus temperature cascade control scheme is finally synthesized and leads even to better performance than the most effective double temperature difference control scheme. These outcomes reveal not only the operation feasibility of the R-DDWDC but also the general significance of the proposed temperature difference plus temperature cascade control scheme to the inferential control of any other complicated distillation columns. 展开更多
关键词 Reactive double dividing-wall distillation column Temperature control Temperature plus temperature cascade control Temperature difference plus temperature cascade control Process operation
下载PDF
Effect of process parameters on microstructure and properties of AM50A magnesium alloy parts formed by double control forming 被引量:4
5
作者 姜巨福 王迎 曲建俊 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第2期321-333,共13页
Effects of process parameters on microstructure and mechanical properties of the AM50A magnesium alloy components formed by double control forming (DCF) were investigated via a four-factor and four-level orthogonal ... Effects of process parameters on microstructure and mechanical properties of the AM50A magnesium alloy components formed by double control forming (DCF) were investigated via a four-factor and four-level orthogonal experiment. The variable curves of DCF showed that the forging procedure was started in the following 35 ms after the injection procedure was completed. It was confirmed that the high-speed filling and high-pressure densifying were combined together in the DCF process. Better surface quality and higher mechanical properties were achieved in the components formed by DCF as compared to die casting (DC) due to the refined and uniform microstructure with a few defects or without defects. Injection speed affected more effectively the yield strength (YS), ultimate tensile strength (UTS) and elongation as compared to pouring temperature, die temperature and forging force. But the pouring temperature had a more significant effect on hardness as compared to injection speed, die temperature and forging force. Pouring temperature of 675 &#176;C, injection speed of 2.7 m/s and forging force of 4000 kN except for die temperature were the optimal parameters for obtaining the highest YS, UTS, elongation and Vickers hardness. Die temperatures of 205, 195, 195 and 225 &#176;C were involved in achieving the highest YS, UTS, elongation and Vickers hardness, respectively. Obvious microporosity and microcracks were found on the fracture surface of the components formed by DC, deteriorating the mechanical properties. However, the tensile fracture morphology of the components formed by DCF was characterized by ductile fracture due to a large number of dimples and no defects, which was beneficial for improving the mechanical properties. 展开更多
关键词 AM50A magnesium alloy double control forming mechanical properties microstructure
下载PDF
EFFECTIVE DOUBLE LOOP CONTROL FOR A SQUARE WAVE BRUSHLESS DC MOTOR
6
作者 周波 李先祥 朱震莲 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1996年第2期34+30-33,共5页
A new type of brushless DC motor has been developed by using a square wave rare earth permanent magnet synchronous motor with its double loop control circuit. The double loop control scheme of the drive system yie... A new type of brushless DC motor has been developed by using a square wave rare earth permanent magnet synchronous motor with its double loop control circuit. The double loop control scheme of the drive system yields a combination of desired characteristics including simplified control structure, small ripple torque, high speed accuracy, wide operating speed range, and fast dynamic response. Experimental results confirm excellent characteristics of the motor. 展开更多
关键词 synchronous motors speed control systems INVERTERS brushless DC motor double loop control square wave motors
下载PDF
Effect of Continuous Application of Controlled Release Nitrogen Fertilizer in Various Types of Soil in Dong-Ting Lake Region under Double Rice Cropping System
7
作者 鲁艳红 廖育林 +3 位作者 聂军 谢坚 杨曾平 戴平安 《Agricultural Science & Technology》 CAS 2012年第2期351-356,379,共7页
[Objective] This study aimed to explore the effects of continuous application of controlled release nitrogen fertilizer under double rice cropping system. [Method] By modeling three types of paddy soils in Dong-Ting L... [Objective] This study aimed to explore the effects of continuous application of controlled release nitrogen fertilizer under double rice cropping system. [Method] By modeling three types of paddy soils in Dong-Ting Lake area, four treatments as no fertilizer (CK), urea, controlled release nitrogen fertilizer (CRNF) and 70% controlled release nitrogen fertilizer (70% CRNF) were designed in the micro-plot trials from 2005 to 2008. [Result] The rice yield in treatment CRNF at N 150 kg/hm2 was increased by 10.3%, 8.0% and 2.4% compared with treatment of urea, in alluvial sandy loamy paddy soil (ALS), purple calcareous clayey paddy soil (PCS), and reddish yellow loamy paddy soil (RYS), respectively; and the yield in treatment of 70% CRNF was increased by 6.1%, 2.6% and -0.8%, respectively. The ranking order of nitrogen uptake amount by plant in early rice and late rice was CRNF 70% CRNF urea CK in all three types of soil. Nitrogen utilization efficiency of CRNF in above three types of soil was 60.7%, 59.6% and 56.3%, increased by 23.8%, 19.4% and 16.3% compared with that in treatment of urea, respectively. Nitrogen utilization efficiency of CRNF in early rice was increased year by year, and was higher than that of 70% CRNF during the whole experiment stage, while that in late rice was increased first and then decreased from the 3rd year. [Conclusion] Continuous application CRNF could alleviate the decreasing of soil nitrogen fertility and organic carbon especially in ALS, increase rice yield and nitrogen utilization efficiency in double-rice cropping system. 展开更多
关键词 double cropping rice controlled release nitrogen fertilizer Continuous fertilization YIELD Fertilizer use efficiency Soil fertility
下载PDF
Novel active fault-tolerant control scheme and its application to a double inverted pendulum system 被引量:3
8
作者 Cui Ping Weng Zhengxin Patton Ron 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第1期134-140,共7页
On the basis of the gain-scheduled H∞ design strategy, a novel active fault-tolerant control scheme is proposed. Under the assumption that the effects of faults on the state-space matrices of systems can be of affine... On the basis of the gain-scheduled H∞ design strategy, a novel active fault-tolerant control scheme is proposed. Under the assumption that the effects of faults on the state-space matrices of systems can be of affine parameter dependence, a reconfigurable robust H∞ linear parameter varying controller is developed. The designed controller is a function of the fault effect factors that can be derived online by using a well-trained neural network. To demonstrate the effectiveness of the proposed method, a double inverted pendulum system, with a fault in the motor tachometer loop, is considered. 展开更多
关键词 active fault-tolerant control neural network estimator gain-scheduled controller double inverted pendulum.
下载PDF
The role of NBS1 in DNA double strand break repair, telomere stability, and cell cycle checkpoint control 被引量:14
9
作者 Ying Zhang Junqing Zhou Chang UK Lim 《Cell Research》 SCIE CAS CSCD 2006年第1期45-54,共10页
The genomes of eukaryotic cells are under continuous assault by environmental agents and endogenous metabolic byproducts. Damage induced in DNA usually leads to a cascade of cellular events, the DNA damage response. F... The genomes of eukaryotic cells are under continuous assault by environmental agents and endogenous metabolic byproducts. Damage induced in DNA usually leads to a cascade of cellular events, the DNA damage response. Failure of the DNA damage response can lead to development of malignancy by reducing the efficiency and fidelity of DNA repair. The NBS1 protein is a component of the MRE11/RAD50/NBS 1 complex (MRN) that plays a critical role in the cellular response to DNA damage and the maintenance of chromosomal integrity. Mutations in the NBS1 gene are responsible for Nijmegen breakage syndrome (NBS), a hereditary disorder that imparts an increased predisposition to development of malignancy. The phenotypic characteristics of cells isolated from NBS patients point to a deficiency in the repair of DNA double strand breaks. Here, we review the current knowledge of the role of NBS1 in the DNA damage response. Emphasis is placed on the role of NBS1 in the DNA double strand repair, modulation of the DNA damage sensing and signaling, cell cycle checkpoint control and maintenance oftelomere stability. 展开更多
关键词 Nijmegen breakage syndrome NBS 1 DNA damage response DNA double strand break cell cycle checkpoint control telomere maintenance
下载PDF
Dynamic Modeling and Adaptive Fast Nonsingular Terminal Sliding Mode Control for Satellite with Double Rotary Payloads 被引量:1
10
作者 Xu Chen Lu Yuping +2 位作者 Yao Keming Liu Yanbin Xiao Dibo 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第3期310-318,共9页
A robust attitude control methodology is proposed for satellite system with double rotary payloads. The dynamic model is built by the Newton-Euler method and then the dynamic interconneetion between satellite's main ... A robust attitude control methodology is proposed for satellite system with double rotary payloads. The dynamic model is built by the Newton-Euler method and then the dynamic interconneetion between satellite's main body and payloads is described precisely. A nonlinear disturbance observer is designed for satellite's main body to estimate disturbance torque acted by motion of payloads. Meanwhile, the adaptive fast nonsingular terminal sliding-mode attitude stabilization controller is proposed for satellite's main body to quicken convergence speed of state variables. Similarly, the adaptive fast nonsingular terminal sliding-mode attitude maneuver controller is designed for each payload to weaken the disturbance effect of motion of satellite's main body. Simulation results verify the effectiveness of the proposed method. 展开更多
关键词 satellite with double rotary payloads multi-rigid-body system sliding mode control disturbance observers attitude control
下载PDF
Remote Control System of 37 mm Double Tube Antiaircraft Gun for Hunan Weather Modification 被引量:1
11
作者 Li Qiong Zhang Zhongbo +2 位作者 Li Zuxian Zhang Yongxiang Zhou Sheng 《Meteorological and Environmental Research》 CAS 2017年第2期33-36,共4页
Hunan Weather Modification Center and Suizhou Dafang Precision Electromechanical Engineering Co.,Ltd. of Hubei commonly transformed and installed 83 double tube antiaircraft guns( 37 mm) of Hunan Province in order to ... Hunan Weather Modification Center and Suizhou Dafang Precision Electromechanical Engineering Co.,Ltd. of Hubei commonly transformed and installed 83 double tube antiaircraft guns( 37 mm) of Hunan Province in order to realize remote control of computer. After transformation,loading capacity of ammunition feeding machine became large,which could shorten the time of filling shells in the case of short airspace time;one shell launch volume was more,which could improve hail suppression effect; the degree of automation was greatly improved,which could save manpower by more than 50%. It fully embodied the modernization level of Hunan weather modification operation. 展开更多
关键词 37 MM double TUBE antiaircraft GUN REMOTE control Automation China
下载PDF
Evaluation matrix with the speed feature based on double inspiriting control lines 被引量:1
12
作者 Weiwei Liu Chunsheng Shi Jing Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第6期962-970,共9页
Methods of the comprehensive evaluation have been studied for many years. However, the change speed of evaluated objects was rarely considered by the existing evaluation methods. An evaluation matrix is proposed to re... Methods of the comprehensive evaluation have been studied for many years. However, the change speed of evaluated objects was rarely considered by the existing evaluation methods. An evaluation matrix is proposed to remedy this deficiency. Firstly, the change speed state (CSS) of the evaluated objects is analyzed based on double inspiriting control lines (DICLs), and a matrix of the CSS is constructed. Then, 72 elements in the matrix are analyzed, and formulas describing each CSS are given. The efficiency of the proposed evaluation matrix is proved when the CSS merges with the change speed trend (CST) in the dynamic comprehensive evaluation. Finally, a computing example shows that the proposed evaluation matrix is feasible in the dynamic comprehensive evaluation with the speed feature. 展开更多
关键词 double inspiriting control lines (DICLs) change speed state (CSS) change speed trend (CST) evaluation matrix
下载PDF
Simulation on model predictive control for PMSM drive system based on double extended state observer 被引量:4
13
作者 CUI Hong-wei TENG Qing-fang +1 位作者 ZHU Jian-guo GUO You-guang 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2018年第4期380-387,共8页
A novel double extended state observer(DESO)based on model predictive torque control(MPTC)strategy is developed for three-phase permanent magnet synchronous motor(PMSM)drive system without current sensor.In general,to... A novel double extended state observer(DESO)based on model predictive torque control(MPTC)strategy is developed for three-phase permanent magnet synchronous motor(PMSM)drive system without current sensor.In general,to achieve high-precision control,two-phase current sensors are necessary for successful implementation of MPTC.For this purpose,two ESOs are used to estimate q-axis current and stator resistance respectively,and then based on this,d-axis current is estimated.Moreover,to reduce torque and flux ripple and to improve the performance of the torque and speed,MPTC strategy is designed.The simulation results validate the feasibility and effectiveness of the proposed scheme. 展开更多
关键词 double extended state observer(DESO) model predictive torque control(MPTC) permanent magnet synchronous motor(PMSM)drive system without current sensor
下载PDF
Synthesis and controlled release of cloprop herbicides from cloprop-layered double hydroxide and cloprop-zinc-layered hydroxide nanocomposites 被引量:1
14
作者 Norhayati Hashim Mohd Zobir Hussein +4 位作者 Illyas Md Isa Azlan Kamari Azmi Mohamed Adila Mohamad Jaafar Hafsah Taha 《Open Journal of Inorganic Chemistry》 2014年第1期1-9,共9页
Two phenoxyherbicide nanocomposites, namely cloprop-layered double hydroxide and cloprop-zinc- layered hydroxide nanocomposites, have been synthesized by using co-precipitation and direct reaction method. PXRD pattern... Two phenoxyherbicide nanocomposites, namely cloprop-layered double hydroxide and cloprop-zinc- layered hydroxide nanocomposites, have been synthesized by using co-precipitation and direct reaction method. PXRD pattern showed an expansion of interlayer spacing with the value of 21.0 &#197;and 22.7 &#197;for cloprop-layered double hydroxide and cloprop-zinc-layered hydroxide nanocomposite, respectively. It is evident from FTIR and elemental analyses that both nanocomposites were successfully intercalated between the interlayers of layered metal hydroxide. Controlled release of cloprop anion from interlayer of nanocomposites for both cloprop-layered double hydroxide and cloprop-zinc-layered hydroxide nanocomposite into phosphate solution was rapid initially and slow thereafter. The percentage of accumulated release of cloprop anion from cloprop-zinc-layered hydroxide nanocomposite was slightly higher than that from cloprop-layered double hydroxide nanocomposite. Kinetic behavior of cloprop release was governed by pseudo-second-order for cloprop-layered double hydroxide nanocomposite while parabolic diffusion for cloprop-zinc-layered hydroxide nanocomposite. Results from this study highlight the potential of both nanocomposites as capsulated material for controlled release of cloprop phenoxyherbicides anion. 展开更多
关键词 Cloprop Cloprop-Layered double HYDROXIDE Cloprop-Zinc-Layered HYDROXIDE NANOCOMPOSITE controlled Release KINETIC Study
下载PDF
Phase Control of Transient Optical Properties of Double Coupled Quantum-Dot Nanostructure via Gaussian Laser Beams 被引量:1
15
作者 J.Shiri F.Shahi +1 位作者 M.R.Mehmannavaz L.Shahrassai 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第2期29-33,共5页
We theoretically analyze the transient properties of a probe field absorption and dispersion in a coupled semiconductor double-quantum-dot nanostructure.We show that in the presence of the Gaussian laser beams,absorpt... We theoretically analyze the transient properties of a probe field absorption and dispersion in a coupled semiconductor double-quantum-dot nanostructure.We show that in the presence of the Gaussian laser beams,absorption and dispersion of the probe field can be dramatically influenced by the relative phase between applied fields and intensity of the Gaussian laser beams.Transient and steady-state behaviors of the probe field absorption and dispersion are discussed to estimate the required switching time.The estimated range is between 5-8 ps for subluminal to superluminal light propagation. 展开更多
关键词 Phase control of Transient Optical Properties of double Coupled Quantum-Dot Nanostructure via Gaussian Laser Beams QDs
下载PDF
Design of Nonlinear Decoupling Controller for Double-electromagnet Suspension System 被引量:9
16
作者 LIU De-Sheng LI Jie ZHANG Kun 《自动化学报》 EI CSCD 北大核心 2006年第3期321-328,共8页
Aiming at the coupling characteristic between the two groups of electromagnets embedded in the module of the maglev train, a nonlinear decoupling controller is designed. The module is modeled as a double-electromagnet... Aiming at the coupling characteristic between the two groups of electromagnets embedded in the module of the maglev train, a nonlinear decoupling controller is designed. The module is modeled as a double-electromagnet system, and based on some reasonable assumptions its nonlinear mathematical model, a MIMO coupling system, is derived. To realize the linearization and decoupling from the input to the output, the model is linearized exactly by means of feedback linearization, and an equivalent linear decoupling model is obtained. Based on the linear model, a nonlinear suspension controller is designed using state feedback. Simulations and experiments show that the controller can effectually solve the coupling problem in double-electromagnet suspension system. 展开更多
关键词 双倍电磁体 解耦 悬浮控制器 反馈控制器
下载PDF
Double-directional control bolt support technology and engineering application at large span Y-type intersections in deep coal mines 被引量:13
17
作者 GUO, Zhibiao SHI, Jianjun +2 位作者 WANG, Jiong CAI, Feng WANG, Fuqiang 《Mining Science and Technology》 EI CAS 2010年第2期254-259,共6页
Under deep and complex geological conditions,severe deformation occurs at intersection points of Y-type roadways with large cross sections during engineering projects in coal mines,especially at junction arches.Based ... Under deep and complex geological conditions,severe deformation occurs at intersection points of Y-type roadways with large cross sections during engineering projects in coal mines,especially at junction arches.Based on in-situ investigations and theoretical studies,we have summarized typical forms of destruction and identified high stress and unrestricted support at both sides of junction arch as its main causes.In this study,we also presented double-directional control bolt support technology for a large Y-type span intersection,applied to deep intersection engineering in the Jiahe Coal Mine,which has proved effective. 展开更多
关键词 Y-type intersection double-directional control bolt support deep coal mines
下载PDF
ON DE FINETTI'S OPTIMAL IMPULSE DIVIDEND CONTROL PROBLEM UNDER CHAPTER 11 BANKRUPTCY
18
作者 王文元 明瑞星 胡亦钧 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期215-233,共19页
Motivated by recent advances made in the study of dividend control and risk management problems involving the U.S.bankruptcy code,in this paper we follow[44]to revisit the De Finetti dividend control problem under the... Motivated by recent advances made in the study of dividend control and risk management problems involving the U.S.bankruptcy code,in this paper we follow[44]to revisit the De Finetti dividend control problem under the reorganization process and the regulator's intervention documented in U.S.Chapter 11 bankruptcy.We do this by further accommodating the fixed transaction costs on dividends to imitate the real-world procedure of dividend payments.Incorporating the fixed transaction costs transforms the targeting optimal dividend problem into an impulse control problem rather than a singular control problem,and hence computations and proofs that are distinct from[44]are needed.To account for the financial stress that is due to the more subtle concept of Chapter 11 bankruptcy,the surplus process after dividends is driven by a piece-wise spectrally negative Lévy process with endogenous regime switching.Some explicit expressions of the expected net present values under a double barrier dividend strategy,new to the literature,are established in terms of scale functions.With the help of these expressions,we are able to characterize the optimal strategy among the set of admissible double barrier dividend strategies.When the tail of the Lévy measure is log-convex,this optimal double barrier dividend strategy is then verified as the optimal dividend strategy,solving our optimal impulse control problem. 展开更多
关键词 spectrally negative Lévy process Chapter 11 bankruptcy De Finetti's dividend problem double barrier strategy impulse control
下载PDF
Integrated design and control technology of liner completion and drilling for horizontal wells
19
作者 GAO Deli XIAN Baoan BI Yansen 《Petroleum Exploration and Development》 SCIE 2024年第4期1009-1021,共13页
Aiming at the problems of large load of rotation drive system,low efficiency of torque transmission and high cost for operation and maintenance of liner steering drilling system for the horizontal well,a new method of... Aiming at the problems of large load of rotation drive system,low efficiency of torque transmission and high cost for operation and maintenance of liner steering drilling system for the horizontal well,a new method of liner differential rotary drilling with double tubular strings in the horizontal well is proposed.The technical principle of this method is revealed,supporting tools such as the differential rotation transducer,composite rotary steering system and the hanger are designed,and technological process is optimized.A tool face control technique of steering drilling assembly is proposed and the calculation model of extension limit of liner differential rotary drilling with double tubular strings in horizontal well is established.These results show that the liner differential rotary drilling with double tubular strings is equipped with measurement while drilling(MWD)and positive displacement motor(PDM),and directional drilling of horizontal well is realized by adjusting rotary speed of drill pipe to control the tool face of PDM.Based on the engineering case of deep coalbed methane horizontal well in the eastern margin of Ordos Basin,the extension limit of horizontal drilling with double tubular strings is calculated.Compared with the conventional liner drilling method,the liner differential rotary drilling with double tubular strings increases the extension limit value of horizontal well significantly.The research findings provide useful reference for the integrated design and control of liner completion and drilling of horizontal wells. 展开更多
关键词 horizontal well liner completion and drilling double tubular strings liner differential rotary drilling tool face control horizontal extension limit
下载PDF
A new control method based on the lattice hydrodynamic model considering the double flux difference
20
作者 Shunda Qin Hongxia Ge Rongjun Cheng 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第5期131-136,共6页
A new feedback control method is derived based on the lattice hydrodynamic model in a single lane. A signal based on the double flux difference is designed in the lattice hydrodynamic model to suppress the traffic jam... A new feedback control method is derived based on the lattice hydrodynamic model in a single lane. A signal based on the double flux difference is designed in the lattice hydrodynamic model to suppress the traffic jam. The stability of the model is analyzed by using the new control method. The advantage of the new model with and without the effect of double flux difference is explored by the numerical simulation. The numerical simulations demonstrate that the traffic jam can be alleviated by the control signal. 展开更多
关键词 traffic flow lattice hydrodynamic model control method double flux difference
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部